Means for automatically controlling the speed of railway-trains.



No. 867,522. PATENTED OCT. 1, 1907.

' 11. J. MoGARTHY.

MEANS FOR AUTOMATIGALLY CONTROLLING THE SPEED OF RAILWAY TRAINS.

APPLICATION FILED APR. 25, 1907.

2 SHEETS-SHEET 1.

No. 867,522; PATENTED 001. f1, 1907. D. J. MoOARTHY.

MEANS FOR AUTOMATICALLY CONTROLLING THE SPEED OF RAILWAY TRAINS.

APPLICATION FILED APR. 25, 1907.

2 SHEETS-SHEET 2' WITNESSES INVENTOR A). Qflfwctk k W, W 7 ASQM to the track curve 4.

ran .sra'rns earner ent ies.

DANIEL J. MCCARTHY, OF WILKINSBURG, PENNSYLVANIA, ASSIGNOR TO UNION SWITCH &

SIGNAL COMPANY, OF SWISSVALE, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA. l

v (rel.

MEANS FOR AUTOMATICALLY CONTROLLING THE SPEED OF RAILWAY-TRAINS.

Specification ofLetters Patent.

Patented Oct. 1, 1907.

Application filed April 251 1907. Serial No. 370,231.

To all whom 'it may concern:

Be it known that I, DANIEL J. MCCARTHY, of.Wil-

kinsburg, Allegheny county, Pennsylvania, have invented a new and. useful Means for Automatically Controlling the Speed of Railway-Trains, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings, forming part of this specification, in which- Figures 1, 2 and 3 are diagrams illustrating one form of my invention; Fig. 4 is a detail sectionaLview of one form of operating device or controller; and Fig. 5 is a diagram showing another form of my invention.

My invention has for its object the automatic control andregulation of the speed of a locomotive or train at points along the right of way where it is deemed unsafe to exceed a certain predetermined speed, as at switches, curves, or in running by distant signals.

My invention consist-sin the provision of means, carried in part by the locomotive or train, and in part located along the track at points where the speed is to be controlled, whereby an electric current is induced in a circuit on the locomotive or train, which circuit includes a brake operating device or controller arranged to apply the brakes to either stop the train or check its speed. 7 Y

My invention also consists in the novel construction, arrangement and combination of parts all substantially as hereinafter described.

Referring to the accompanying drawings, the numeral 2 designates a series of magnet poles which are wound with coils 3 in such a manner asto produce opposite polarity of alternate poles. A series of these electro-magnets are placed adjacent to the track wherever the speed is to be regulated or controlled. Thus, in Fig. 1 I- have shown one series adjacent to a branch or turnout, and another series on an approach 5 designates an induction coil which is wound upon a suitable magnetic core mounted upon the locomotive or car. of a train in such a manner as to travel in close proximity to the polar faces of the magnets 2 when the locomotive'or car is passing the same. Included in the circuit 6 of this coil is a device or controller 7, which operates the controlling mechanism of the locomotive, which may beeither the brakes, or. the throttle valve, or both. As the coil passes these electro-magnets, an electro-motive force is generated in the coil,

accomplished in the following manner:-The controller 7 which operates, when energized, the controlling mechanism ofthe locomotive, may be so designed as to operate only at an electro-motive force above a certain predetermined value, being inoperative by an electro-motive force of any lower .value. As the electro-motive force generated in a conductor cutting lines of force, is proportionalto the rate of cutting, it

follows that the .electro-motive force which will 'begenerated in the coil 5 as it passes through the mag netic field produced by the electro-magnets, will-'de pend upon the rate at which it cuts the magnetic flux of this field. This can be expressedby the formula in which E equals the electro-motive force to be generated in the coil 5 necessary to operatethe controller 7; N the number of lines of force out by said coil; and t'the time in seconds taken to cutthe lines of force N. If E remains constant, any change in N will make a corresponding change in t; if the value of N- is lowered, the value of t will also be correspondingly lowered, and vice versa; so that if the value .of N is lowered, the coil 5 will have to pass-over the pole facesof the magnets in a, correspondingly shorter time in order to have the necessary ele'ctromotive force generated therein to operate the controller 7. This allows a higher speed to the motor or car carrying this coil. If the value of N is raised, the speed at which the coil 5 travels over the magnets will be correspondingly slower in producing the same electro-motive force, thereforeby altering the capacity of the battery 9, which energiz'es the magnets; or, if the source of current supply might be an unsafe speed for a freight train. This con-.

dition canbe governed by equipping the freight locomotive with a controller 7 which will ,work at a lower electro-motive force than that of the controller on pas-' senger trains; orby changing the number of turns in the coil 5 the same result may be obtained, a smaller coil will be an alternating current, the frequency of which will depend upon the number of poles passed over in a given time, or equal to the number of pairs of poles passed over per second, as expressedby the following formula in which P equals the number of poles, S the time in seconds in which the coil 5 moves over these poles, and N the frequency per second. If the frequency is constant, anychange in P will make a corresponding change in S. This fact may also be taken advantage of to regulate the speed of the locomotive or train by so designing the controller 7 that it will operate only on a frequency higher than a certain predetermined ire. quency. The changing of the number of poles in a given space over which the coil 5 passes, will also permit different speeds at various points on the right of way. That is to say, any desired speed limit can be maintained by placing the proper number of poles in a given space, corresponding to the speed at which the coil 5 is to pass over them to produc e the proper frequency for the operation of the controller 7.

In Fig. 5 I have shown another means of operating the controller 7 by an alternating current. In this figure 10 and 11 designate the two track rails. 12 is a conductor placed adjacent to one of the track rails and divided into short separated sections. Alternate ones of these sections are connected together by means of conductors 13, and one of the end sections is connected by a conductor 14 with one terminal of a battery 15, whose other terminal is connected to one of the track rails. The locomotive or car carries a transformer, whose primary coil 16 is connected to the track rails through the carwheels 17 and to the conductors 12 through a sliding contact 18. The secondary coil 19 of this transformer is in the circuit of the controller 7. As the sliding contact 18 moves over the conductors 12 a pulsating current is sent through the primary coil 16 of the transformer, which induces an alternating current in the secondary 19, the frequency of which depends upon the rate ofspeed at which the contact 18 passes over the conductors 12.

In Fig. 4 I have shown one form of the controller 7.

20 designates a coil either of a solenoid or other form of magnet, which is connected in the circuit of the induction coil 5 or with the secondary coil 19 of the trans former of Fig. 5, as before described. The armature core 21 of this coil 20 is connected to a plunger 22 work exhaust port 30.

ing in a valve casing 23 against a spring 24. The normal position of this plunger is as shown in Fig. 4. When the coil 20 is energized by a current to which it is responsive, theplunger 22 is moved against the spring 24 into a position where its port 25 will connect the port 26 with the cylinder chamber 27. The port 26 is connected with the train line pipe of the air brake system. In the cylinder chamber 27 is a piston valve 28, which is normally held by a spring 29 in position to close an When the piston is operated as above described to application of the brakes. The plunger 22 is locked I in this position by means of the spring-pressed pawl 31 which engages the notch or recess 32 in the plunger.

33 designates a cylinder which is connected to the valve casing 23, in which is a piston 34 which is normally held towards the outer end portion of the cylinder against a spring 35, by means of air pressure admitted thereto by way of the port 26, the port 36 in the plunger and the port 37, leading from the plunger to the cylinder. Extending through this port 37 into the cylinder is a rod 38 which also extends through a slot in the plunger into contact with the pawl or dog 31. When the pressure of the train line is reduced to the proper amount, the valve 28 is resented by the spring 29, but will be again opened if the pressure. in the chamber 27 rises enough to compress the spring 29, thus insuring the reduction of the train line, pressure to the desired point at which itv will remain constant. The amount of the reduction may be governed by adjustingthe spring 29.

When the plunger 22 has been operated as above described, the port 36.is moved so as to overlap an exhaust port 39 in the valve casing, thereby permitting air to exhaust from the cylinder 33 by way oi the ports 36, 37 and 39. This reduces the pressure in cylinder 33 and permits the spring 35 to force the piston 34 into contact with the end of the rod 38. This forces the pawl 31 out of engagement with the plunger 22 and permits the spring 24 to restore said plunger to its normal position. By altering the size of the port 39, the time taken by the piston 34 to complete its stroke can be made longer or shorter, as desired, thereby governing the length of time during which the brakes are applied.

The system herein described does riot permit of any operation of its parts by the engine man or other op ator on the train. The, only operation which the e gine man-is required to make, is to place the brake valve handle in the release position so as to release the brakes after they have been applied in the manner above described. It is immaterial whether this'lever is put into releasing position before or after the application of the brakes takes place, since the brakes cannot be released until the piston 34 has completed its stroke and released the plunger 22. It will thus be seen that my invention provides means'whereby the speed of a locomotive or train can be automatically controlled at any desiredpoint along the right of way, or within any desired limits, different speeds being permissible for different trains, if desired.

\ My invention is susceptible to various modifications by those skilled in the art. Thus, any suitable means may be provided for inducing a current in the circuit of the controller; and the latter can consist of any form 'for generating an alternating current for, actuating said controller, an electro-magnetic device for operating the responsive only to a current having .a frequency aboua valve of the engine, or to both the throttle valve and to a brake-applying valve.

What I claim is:-

1. In speed-controlling mechanism for trains, a brakecontrolling valve, a magnet for opening said valve, .an energizing circuitvfor said magnet on the locomotive or train, and means whereby the movement of the train beyo nd a predetermined speed is caused to generate a current of proper character to energize said circuit at predetermined places along the road; substantially as described.

2. In speed-controlling mechanism for trains, a speedcontrolling device, an electro-magnetic device for operating the same, and responsive only to a current having a frequency above a predetermined limit, and inductive means device at predetermined places along the road, substantially'as described? 3. In speed-controlling mechanism for trains, a speedcontroller to reduce the speed of the train, and means for inducing a current in the circuit of said device, said means being carried in part by the train and in part" located along the -trackway, said electro-magnetic' device. being certain predetermined frequency; substantially as described.

4. In apparatus for the purpose described, a speed controller, an electro-magnetic means for operating said controller to reduce the speed,-means'fo r inducing current in the circuit of said device by the movementof the train past predetermined points, and means for automatically returning the speed controller to said normal position; substantially as described.

5. In apparatus for the purpose described, a speed-controlling device, an electro-magnetically operated actuating device therefor, anv induction coil in the circuit of said device, and means along' the right of way for inducing a circuit in said coil oii'a certain frequency at a' predetermined speed of the train; substantially as described.

6. In apparatus of the character described, a speed controlling device, electro-magnetic operatingmeans therefor, an induction coil in the circuit of said means, and electromagnets adjacentto the right of way adapted to induce a current in said coil and spaced at such distances'as to cause a given frequency to such current at a 'given speed of the train; substantially as described,

7. In apparatus of the character described, a speed con-- trolling device, an electro-magnetically operated actuator ,valve means in open position, and means for releasing the lock after a predetermined time interval; substantially as described.

9. A speed controllingdevice connected with the brake system of a locomotive or train, and having an escape opening, valvenmeans controlling said opening, an electromagnetic device for operating the valve means in one direction, spring'means for operating the valve means in the other direction, a lock for the valve means, and a pneumatic device for releasing said lock after a predetermined time interval; substantially as described.

In testimony whereof, I have hereunto set my hand.

DANIEL J. MCCARTHY. Witnesses:

JOHN D. Tums,

Enmna R. Con. 

